Page 193 - Sustainable On-Site CHP Systems Design, Construction, and Operations

166 De s i g n

As discussed in Chaps. 3 and 4, some of the major CHP equipments include
• Prime movers [e.g., combustion turbine generators, engine-driven generators,
microturbines, fuel cells (which is not a prime per se), or other CHP technology]
• Heat recovery units (e.g., HRSG or hot water heat recovery units)
• Thermal-powered chillers (e.g., steam turbine–driven centrifugal chillers or
absorption chillers)
• Pumps (e.g., boiler feedwater pumps, jacket water pumps, condensate pumps,
chilled water pumps, condenser pumps, or hot water pumps)
• Heat exchangers (e.g., engine jacket water is often isolated from a hot water
hydronic system by a water-to-water heat exchanger as it would be costly to
supply chemicals, e.g., glycol, for the whole hydronic system)
• Emissions reduction equipment

The basic materials and methods section of the specifications includes material such
as concrete, reinforcing bars, piping for each system and use including buried and
exposed (e.g., natural gas, steam, condensate, hot water, chilled water, condenser or
cooling water, lube oil, vents, drains, and engine exhaust), ductwork (e.g., combustion
air intakes and combustion turbine exhaust), HRSG or alternate heat recovery system,
as well as pipe supports. Specifications are also required for all electrical work (e.g.,
conduit and wire, substations, switchgear, motor control centers, switches, and grounding)
and for the prime mover and plant control systems, which must be integrated for the
effective control and optimization needed to help achieve CHP sustainability. If a new
building enclosure is being constructed to house the CHP system, specifications will be
required for building components such as doors, windows, roofing, sealants, and paint.

Working Drawings (Construction Documents)
The final working drawing phase encompasses the detailed design effort and is
typically divided into 50 percent construction documents (CDs) 95 percent CDs, and
100 percent CDs (plan-check set). The specific percent of completion varies depending
on the desires of the owner-operator. Each phase should develop a check set for the
owner-operator, estimator and each engineering discipline to review and comment. All
comments should be addressed before proceeding to the next phase. Typically, the final
plan-check set should be stamped, sealed, and signed by the CHP team design profes-
sionals before submittal for permits by the authorities. Any changes from that point on
require approval by all code and permit authorities.
The 100 percent CDs should contain all required architectural drawings (if new build-
ing facilities or major building renovations are contemplated), civil drawings for building
grading and utility connections, structural drawings showing equipment and piping sup-
ports (and any new building work), piping system schematics, mechanical drawings for
the CHP system itself, and electrical drawings detailing the generator interconnection,
protection, and grounding (see Chap. 11). Further, the 100 percent CDs should essentially
be complete, coordinated, code compliant, biddable, and constructible. At a minimum,
the 100 percent CDs include: a title sheet with project location plan and drawing index; a
site plan; schematic flow and instrumentation diagrams; and for each discipline any
required demolition plans, installation floor plans, elevations, sections, details, and sched-
ules necessary to show how to construct the proposed CHP system.